A Journey Through the Flames of War in the Republican Era

Song Hongfei knew that in later generations, people's work and life would be inseparable from electronic computers.

Early analog computers were primarily used for numerical calculations, which were limited in function and slow in processing speed.

Through continuous innovation and improvement by numerous scientists building upon the work of their predecessors, and by applying Boolean algebra and logic gate circuits, modern electronic computers have transformed from simple computing tools into truly versatile "general-purpose tools" capable of solving a wide range of problems.

If the problem is complex, in Boolean algebra, this means adding operators and variables; in circuits, it simply means adding combinations of gate circuits.

Historically, it was Shannon's research that linked Boolean algebra with switching circuits, using Boolean algebra to analyze and optimize switching circuits, laying the theoretical foundation for digital circuits and solving the theoretical problems of modern electronic computers.

Song Hongfei combined his work on improving the "electronic" version of the MIT differential analyzer with a deep dive into Boolean logic algebra and electronic circuit design from scratch.

As a later PhD in Electronic Information, he had never read Shannon's paper, just like knowing that 1+1=2 but never investigating why.

Song Hongfei further expanded and supplemented Shannon's paper, and focused on strengthening the theoretical proof of the use of binary in computers.

Song Hongfei's research integrates Boolean logic and binary code into the design of switching circuits, elucidates the relationship between symbolic analysis in relays, vacuum tubes, and switching circuits, and perfectly connects Boolean algebra, binary code, and switching circuits.

The application of relays and vacuum tubes paved the way for the design of logic gate circuits. These electronic components have one thing in common—they are all circuit switches that can be controlled to open or close.

The binary digits "1" and "0" are cleverly mapped to the Boolean logic values ​​"true" and "false," and remarkably, these correspond precisely to the "on" and "off" states in a relay circuit. This allows switching circuits to simulate logical states, forming "logic gate" circuits—a truly ingenious design!

The binary arithmetic rules are naturally and perfectly suited to Boolean logic. In logic gate circuits, using binary numbers "1" and "0" to represent "on" and "off" is a perfect match. This is the essence of using binary.

There are three basic logic gates in logic circuits: AND gate, OR gate, and NOT gate, which correspond to the three basic logic operations in Boolean algebra: NOT, AND, and OR.

By combining these three basic logic gates in different ways, all logical operations can be implemented. They can also perform a series of arithmetic operations, such as adders and multipliers, and thus can be further constructed to realize more complex and general calculations, helping humans solve various problems.

Song Hongfei couldn't help but recall the words of Lao Tzu, an ancient Chinese sage: "The Tao gives birth to One, One gives birth to Two, Two gives birth to Three, and Three gives birth to all things!"

"What a wonderfully similar approach!"

Song Hongfei was overjoyed and exclaimed, "The world is truly amazing!"

Furthermore, logic gates have a remarkable property: through simple and ingenious combination design, logic circuits can have a memory function, and the circuits also have storage capabilities!

Because people have long been accustomed to the decimal system as a common counting method, early mechanical and electromechanical analog computers generally adopted a decimal design, such as using the number of gears to represent decimal. The circuit design was very complicated and troubleshooting was very difficult.

With the development of electronic technology, people have found that binary code is increasingly in line with the design principles of computers and circuits.

Song Hongfei's research has proven that binary has great power, with good stability, high reliability, simple operation, and strong versatility. In addition, the circuit structure is simple and the circuit design and debugging are convenient.

He further argued that using binary encoding based on the modular arithmetic principle, such as sign-magnitude, inverse code, and complement code, can more easily and quickly handle positive and negative signs, borrowing and carrying, and is more suitable for mathematical operations. Data storage and calculation can both be implemented based on binary.

Song Hongfei proposed that Boolean algebra can solve all the operational rules and symbol problems of binary. Using binary as the number system has huge advantages and significance. Electronic computers are naturally suitable for binary encoding, operation and storage.

In his paper, he also put forward a general idea that the development trend of modern electronic computer technology will be that data and programs will be stored in "memory" in binary form, and the main way to use computers in the future will be to write and run programs—which also cleared the theoretical obstacles for the final proposal of the concept of memory.

This is the "stored program principle," a landmark and revolutionary development in the history of computer development. Historically, it was proposed by John von Neumann and others in June 1945 and is known as the "von Neumann architecture."

Song Hongfei's groundbreaking paper has attracted worldwide attention, shocked the scientific community, and caused a great stir in countries around the world.

Song Hongfei gained fame in Europe and America. His research results were praised by many experts and scholars as laying the theoretical foundation for modern electronic circuit technology and having historical guiding significance.

After graduating from West Point with his undergraduate degree, Song Hongfei earned his master's and doctoral degrees from MIT in just three years, which is an incredible feat.

Even the proud Europeans and Americans had to abandon their previous contempt for the Chinese people, and they expressed high praise for the outstanding achievements of this young Chinese scholar.

Professor Vannevar Bush was incredibly proud, stating, "Hongfei's talent amazes and impresses me immensely. His outstanding performance and achievements at MIT have exceeded my expectations for MIT's best doctoral students. I must say, he is just as amazing as Dr. Gu Yuxiu, who earned his bachelor's, master's, and doctoral degrees from MIT in four and a half years!"

[Note: Gu Yuxiu went to the United States to study in 12, and in four and a half years she successively obtained her bachelor's, master's and doctoral degrees, becoming the first Chinese person to obtain a Doctor of Science degree in the Department of Electrical Engineering at MIT.]

Various honors came one after another, bringing Song Hongfei great fame and glory. The media and industry praised him as a rising star of scientific talent, and some even called him a genius PhD from MIT.

He was invited by numerous universities and research institutions to give lectures and presentations, keeping him extremely busy.

Song Hongfei, however, declined all invitations with unusual humility, continuing his work and life as usual, and continuing his research on the "intermediate-power ammunition gun family".

What outsiders don't know is that Song Hongfei is carrying out several top-secret research projects, a fact he has to take seriously. Everything must be kept strictly confidential, as being too prominent attracts attention and he needs to keep a low profile.

In fact, the Military Commission had informed him that his reputation and achievements over the years had gradually become apparent, and that he had likely come under the close surveillance of the intelligence agencies of the Eastern Kingdom.

Perhaps due to his early training in traditional Chinese martial arts, he possesses a far more acute sense of touch than others, giving him a keen awareness of potential dangers lurking in his surroundings. The feeling of being secretly watched makes him very uncomfortable.

Time flows like a song, and years pass like water.

Before I knew it, seven years of my study abroad life in the United States had passed, and the day to return home had arrived.